What does your use of the word “I” say about you?

It indicates status:

“People across the board think that Obama uses the word ‘I’ at incredibly high rates, but if you do an analysis he uses the word ‘I’ at lower rates than any modern president, by a lot,” Pennebaker says.

Comparably, former Presidents Bill Clinton and George W. Bush used “I” at very high rates. Pennebaker finds that people who use “I” at higher rates tend to come across as more personal, warm and honest. While people who use “I” at lower rates come across as more self-confident. He attributes people thinking of Obama using “I” at such high rates, due to his self confidence and the misconception that confident people must use “I” all the time. He also finds that the highest status person in a relationship tends to use “I” the least, and the person who is the lowest status tends to use the word “I” the most.

“I” use can also help you tell if someone is lying:

In other studies, Pennebaker has helped to develop a linguistic lie detector. Within a group of college students, half were prompted to lie. According to the study, people who are telling the truth demonstrate a different language profile than those who are lying. Detection was much better than chance, with 67 percent accuracy.

“One way you can tell if people are telling the truth, they use ‘I’ more. They use more complex language,” Pennebaker says. “People who are lying tend to not use the word ‘I.’ They are psychologically distancing themselves. And they also avoid markers of complexity such as conjunctions and prepositions.”

Pennebaker’s research on word use also extends to the dating arena:

Pennebaker applies some of his language findings to love. Using a speed dating study, he and his team looked at language style matching, which is how function words are being used at a comparable rate between a couple. According to the study, those people whose language styles most frequently matched were much more likely to go on a subsequent date.

“We did a better job predicting if they would go on a date than they did themselves,” Pennebaker says. “This style-matching statistic tells use how the two are clicking with one another. The more likely they were to match in future text messages and instant messages, the more likely they were to still be dating several months later.”